Divided thumbpiece latch

ABSTRACT

A handle and latch assembly for a door having a thumbpiece actuating a retractable latchbolt from engagement with a strike. A generally upright handle is mounted on the door with the thumbpiece having a single actuating shank behind the upper end of the handle and a divided or bifurcated thumb-engaging portion extending around and outwardly of the upright handle with the bifurcation allowing movement of the thumbpiece relative to the handle.

I Umted States Patent i 1 1 3,591,224

72 Inventor Robert K. [later [56] References Cited UNITED STATES PATENTS P 8613 2,266,106 12 1941 VoightQ 1. 292/167 x 1221 F1led Sept. 26, 1969 2 2,483,368 9/1949 Ledm 292/165 2 :52:: z fa zg and Industries he 2,485,054 10/1949 Lichteig 292/165 g Paglia l 2,905,497 9/1959 Bower 292/3363 3,257,138 6/1966 Russell 292/3363 Primary Examiner-James A. Leppink Assistant Examiner-Edward J. McCarthy Allqrl1y-Wlls0n & Geppert [S4] DlVlDED THUMBPIECE LATCH 2 Clams 5 ABSTRACT: A handle and latch assembly for a door having a [52] US. Cl 292/336.3, thumbpiece actuating a retractable latchbo'lt from engage- 292/167 ment with a strike. A generally upright handle is mounted on [51] Int. Cl EOSb 3/00, the door with the thumbpiece having a single actuating shank E05c 1/12 behind the upper end of the handle and a divided or bifurcated [50] Field of Search 292/3363, thumb-engaging portion extending around and outwardly of 165, 166; 167, 173, 139, 193. 19,1, 196, 200, 217, the upright handle with the bifurcation allowing movement of 226, 236 the thumbpiece relative to the handle.

l jzfl Z PATENTED JUL SIS?! 3.591; 224

DlVlDED THUMBPIECE LATCH The present invention relates to a novel latch assembly for a door and more particularly to a handle and latch assembly having a manually actuable divided thumbpiece.

Among the objects of the present invention is the provision of a door latch assembly having an immovable handle and a rockable or pivotal thumbpiece adapted to be manually actuable to retract a latchbolt from a suitable strike. The thumbpiece is formed with a central shank extending through a backplate on the door to the latching mechanism and a divided or bifurcated thumb-engaging portion generally encompassing the handle to allow pivotal movement of the thumbpiece relative to the handle.

Another object of the present invention is the provision of a handle and latch assembly including a generally upright elongated handle adapted to be grasped by the hand of the operator or user and a divided or bifurcated thumbpiece having a central shank located behind the handle adjacent the upper end thereof to provide a compact assembly. The bifurcated portion of the thumbpiece extends around the handle to allow for ease of engagement and actuation by the operator and for movement to retract the latchbolt.

A further object of the present invention is the provision of a door handle and latch assembly with a stationary handle and a divided thumbpiece which pivots and moves relative to the handle. The bifurcations of the thumbpiece extend around and outwardly of the handle at each side thereof to allow for ease of actuation by either a rightor left-handed person opening the door.

Further objects are to provide a construction of maximum simplicity, efficiency, economy and ease of assembly and operation, and such further objects, advantages and capabilities as will later more fully appear and are inherently possessed thereby.

In the drawing:

FIG. 1 is a front elevational view of a'handle and thumbpiece latch assembly for a door.

P10. 2 is a side elevational view of the assembly of FIG. 1 showing the latchbolt in the edge of the door.

FIG. 3 is a top plan view of the assembly of FIG. 1 with the door broken away.

P10. 4 is a rear elevational view of the latch mechanism taken on the line 4-4 of P10. 3 and showing the latchbolt in dotted outline.

FIG. 5 is a view similar to FIG. 4 but with the thumbpiece depressed and the latch-actuating shank rotated 90 to retract the latchbolt.

Referring more particularly to the disclosure in the drawing wherein is shown an illustrative embodiment of the present invention, FIG. 1 disclosed a door 10, as for an entrance to a house or the like, having a free edge 11 movable into engage ment with a doorjamb (not shown) and having a retractable latchbolt 12 adapted to engage and be received in a suitable V strike plate mounted on the doorjamb. The latchbolt 12 is mounted in a tubular housing 13 and resiliently biased to latching position by a compression spring 14. A slide plate 15 is secured to the latchbolt l2 and extends rearwardly through the housing 13 into a retractor housing 16 and terminates in a pair of ears 17 having intuming ends 18. A retractor 19 is rotatably mounted in the housing 16 and is provided with an arcuate enlargement 21 forming a pair of shoulders 22 normally engaging the ends 18. Rotation of the retractor 19 in either direction causes the enlargement 21 to engage one of the two ends 18 to retract the slide plate 15 and latchbolt 12 against the force of the spring 14. The retractor 19 has a square opening axially therethrough to receive a square shank 23 to be later described.

On the exterior surface 24 of the door is mounted a lower backplate 25 and an upper backplate 26 by suitable securing means (not shown). An elongated handle 27 has a central gripping portion 28 between a pair of rearwardly extending posts 29,29 secured to the backplates 25 and 26 and is generally upright relative to the door 10 so as to be easily grasped by a person wishing to open the door. Mounted for rockable or pivotal movement in the upper backplate 26 is a thumbpiece 31 having a central stem 32 with a notch 33 in the underside to provide a pivot fulcrum, and a rearward lifting surface 34 extending into a recess 35 formed in the rear surface of the backplate 26.

The exposed outer portion 36 of the thumbpiece 31 is widened and thickened compared to the central stem 32, and the edges 37 gradually diverge away from the backplate 26. For approximately the outer one-half of the portion 36, the thumbpiece is divided or bifurcated by a generally U-shaped recess 38 to provide spaced outer arms 39,39. As especially seen in FIGS. 1 and 3, the arms 39,39 generally encompass the upper end 41 of the handle 27 just above the upper post 29 to allow movement of the thumbpiece 31 relative to the stationary handle 27.

Within the recess 35 in the upper backplate 26 is secured by suitable means, such as the screw 42, a pair of mounting plates 43 and 44. The lower plate 43 is generally channel shaped and includes a lower projecting car 45 and an opening 46 receiving the stem 32 of the thumbpiece 31 with the notch 33 engaging the lower edge ofthe opening 46. The upper flat plate 44 is approximately one-half of the length of the plate 43 and has a central notch 47 to allow upward movement of the lifting surface 34 of the thumbpiece. The square shank 23 has a flattened portion 48 adjacent the plate 44 and then has a reduced diameter to pass through an aligned opening in the plate 44 and the end is staked to secure the shank 23 to the plate 44 for rotation.

A pair of internally threaded posts 49,49 extend from and are riveted to the plates 43,44 and extend at least partially through the door 10 to receive threaded fasteners in a suitable escutcheon plate (not shown) on the interior surface of the door. Also, the shank 23 extends through and beyond the door to be received in a suitable interior knob for actuation of the latchbolt 12 from the interior of the door.

The flattened portion 48 of the shank 23 is conformably received in a slot of an irregularly shaped plate 51 having an offset 52 to receive a pivot rivet 53 connecting the plate 51 to one end of a curved link 54. The opposite end of the link has an elongated slot 55 receiving a connecting rivet 56 which is also connected to the free end of a lift link 57. The link 57 is pivoted on a stationary rivet 58 secured to the plate 44. The link 57 has a horizontal flange 59 engaging the lifting surface 34 of the thumbpiece 31, and a spring -61 has one end secured to the ear 45 of the plate 43 and the opposite end secured to the flange 59 to bias the link 57 downward in a clockwise direction about the rivet 58 as seen in FIGS. 4 and 5.

In use, a person wishing to open the door 10 from the exterior grasps the central portion 28 of the handle 27 and manually depresses the thumbpiece 31 with his thumb to retract the latchbolt 12. The thumbpiece 31 pivots or rocks at the notch 33 of the stem 32 to raise the lifting surface 34. The surface 34 engaging the lift link 57 causes the link to pivot counter clockwise around the rivet 58 with the rivet 56 engaging the upper end of slot 55 to raise the curved link 54. Upward motion of the curved link 54 causes counterclockwise rotation of the irregularly shaped plate 51 and the shank 23 (FIG. 5). Rotation of the shank 23 causes rotation of the retractor 19 to retract the latchbolt 12 against the force of the compression spring 14. Upon release of the thumb latch 31, the spring 61 causes clockwise rotation of the link 57 to return the mechanism to the normal position of FIG. 4.

The elongated slot 55 allows movement of the curved link 54 and rotation of the plate 51 and the shank 23 relative to the lift link 57 which is normally biased downward. This slot provides a lost motion action so that rotation of the inner knob (not shown) will rotate the shank 23 to retract the latchbolt 12 without movement of the thumbpiece 31 or the lift link 57. The shank 23 can be rotated in either a clockwise or counterclockwise direction with the lost motion action permitting shaft rotation. The divided portion of the thumbpiece 31 providing the outer arms 39,39 allows ease of actuation by either a rightor left-handed person. Also, the divided thumbpiece permits the placement of the thumbpiece in a position other than above the upper end of the handle.

Having thus disclosed my invention, I claim:

1. In a latchbolt assemblyfor a door, the combination of an elongated upright handle secured to the door, and a thumbpiece pivotally mounted in the door behind the upper portion of the handle and spaced from the ends of the handle, said thumbpiece having a central rearwardly extending stem and a wider exposed forward portion with diverging edges, and thumbpiece being bifurcated at the front edge by a U-shape notch into a pair of arms extending outwardly at both sides of and generally encompassing and spanning the upper portion of the handle with said handle projecting through said notch to provide for pivotal movement of the thumbpiece relative to the handle.

2. In a latchbolt assembly as set forth in claim 1, in which a pair of spaced backplates are secured to the door with the handle being secured to said backplates; the central stem of said thumbpiccc extending through one of said backplates and into cooperative engagement with actuating mechanism for a latchbolt, said central stem having a notch on its lower surface acting as a fulcrum and a lifting surface on its upper surface cooperating with the actuating mechanism. 

1. In a latchbolt assembly for a door, the combination of an elongated upright handle secured to the door, and a thumbpiece pivotally mounted in the door behind the upper portion of the handle and spaced from the ends of the handle, said thumbpiece having a central rearwardly extending stem and a wider exposed forward portion with diverging edges, and thumbpiece being bifurcated at the front edge by a U-shape notch into a pair of arms extending outwardly at both sides of and generally encompassing and spanning the upper portion of the handle with said handle projecting through said notch to provide for pivotal movement of the thumbpiece relative to the handle.
 2. In a latchbolt assembly as set forth in claim 1, in which a pair of spaced backplates are secured to the door with the handle being secured to said backplates, the central stem of said thumbpiece extending through one of said backplates and into cooperative engagement with actuating mechanism for a latchbolt, said central stem having a notch on its lower surface acting as a fulcrum and a lifting surface on its upper surface cooperating with the actuating mechanism. 